Effect of Porous Seepage on Lubrication Performance of Circular-Face Bilayer Oil Bearing

The percolation characteristics of oil in the porous bearing have a significant effect on the lubricating performance of the oil film. Taking the bilayer oil bearing with different porosity as the object for research, its percolation characteristics in porous medium were described based on Darcy's law. And the bilayer oil bearing seepage lubrication model was established in polar coordinates. The oil film pressure distribution in the bilayer bearing system was studied. The influence of the structural parameters and the seepage behavior on the lubrication performance were analyzed. The hydrodynamic pressure mainly occurred between the annular friction surfaces. From the friction interface to bearing bottom face, the fluid pressure gradually transmitted from the outer edge to the center, the pressure area increased and the pressure peak decreased gradually. With the increase of obliquity, the hydrodynamic pressure effect between friction interfaces was enhanced, and the lubricating performance was improved. The decrease of the surface thickness or porosity weakened the seepage effect between frictional interfaces. Hence, the lubricating performance was improved. Compared with ordinary single layer oil bearing, bilayer oil bearing reduced the whole porosity, prevented oil infiltrating into the porous medium, and had better lubricating performance. The research provided a theoretical basis for clarifying the lubrication mechanism and seepage behavior of bilayer oil bearing.